The energy consumption is usually their downfall. The electricity companies detect a massive draw in the area then cross ref with premises and identify the premises causing the issue. A quick magistrates warrant and in goes the door. Invariable there are one or two young Vietnamese tending the plants who are too scared to "grass" on the bosses. The money then gets laundered through nail bars and the like. A little human trafficking plus a bypassed lecky meter and away you go.
As an SOP, I wanted our force helicopter to fly back to base from any deployment with its FLIR thermal camera on but that's not allowed apparently. You can't just prospect from the night sky.